When the Arabs conquered Egypt, the desire arose for a direct communication by water to Arabia, and the fresh-water canal which connected the Nile with the Red Sea was cleared. Corn was now shipped on the Nile for Djar, the port of Medina, where goods coming from India and China were disembarked and re-shipped for Egypt. But owing to a dispute between the ruler of Egypt and his uncle at Medina, in the year 775, the port of Djar was closed to the Egyptians. The ships bearing Eastern goods for Egypt for a time landed at Roman Clysma, near Suez, which secured a new lease of life as Arabic Kolzoum. But Kolzoum like Arsinoë, silted up, while Suez as a port was not yet in being. On the west coast of the peninsula of Sinai lay Raithou, near which a landing stage offered the advantages of a natural harbour. Ships therefore landed near Raithou, called Raya by the Arabs, where the goods were transferred to camel-back for conveyance to Cairo and Alexandria. The monks of the convent of Sinai were in direct connection with the monks at Raithou, who owned large palm groves, and doubtless controlled the landing stage. For the place which here grew up came to be known as Tur, an Arabic word signifying height, which was first applied to the convent of Sinai. Mukaddisi (_c._ 985) mentioned Tur Sina and noted that the Christians had a convent there, and some well-cultivated fields, and olive trees of great excellence.[239] The Christians called it Porta Santa Katerina or simply Santa Katerina (1383). The use of Tur as a port brought the Sultan of Egypt into relation with the monks, and acted as a safeguard to the convent. In 1010 the Saracens bore down on the Church of the Holy Sepulchre at Jerusalem and destroyed it. They then moved on to Sinai with the intention of destroying the convent also, but they were warned off by seeing the mountain aglow with fire. The chronicler, Ademar, stated that when the report of the proposed attack reached the Sultan, he and his Saracens repented.[240] An attack on the port of Aila may have caused a further deviation of trade to Tur. Makrizi († 1441) recorded that Aila was pillaged by Abd Allah ben Edirs ben Dgofair, governor of El Korah, with the help of the Benu el Garrah.[241] This put a stop to the transit of goods via Aila to Damascus, and the Eastern goods for Syria as well as those for Egypt were now disembarked at Tur. This change is reflected in the fact that Tur, sometime between 1020 and 1050 took the place of Kolzoum as a customs station, although it remained for some time so poor a place that the appointment there was considered equal to a disgrace.